#include <bits/stdc++.h>
using namespace std;

#define int long long
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define fi first
#define se second

const int MAXN = 300'001;

bool vis[MAXN];
int vx[MAXN], vy[MAXN];
vector<pair<int, int>> g[MAXN];
int ptr[MAXN];
bool del[MAXN];
int ans[MAXN];
int deg[MAXN];

bool phase_1;
bool xit;

void dfs(int cur, int col = 0) {
    while(ptr[cur] < g[cur].size()) {
        if(xit) {
            return;
        }
        int nei = g[cur][ptr[cur]].fi;
        int id = g[cur][ptr[cur]].se;
        if(del[id]) {
            ptr[cur]++;
            continue;
        }
        del[id] = true;
        ans[id] = col;
        deg[cur]++;
        deg[nei]++;
        ptr[cur]++;
        dfs(nei, 1 - col);
    }
    if(phase_1) {
        xit = true;
    }
}

void solve() {
    int n; cin >> n;
    vector<int> comp1, comp2;
    for (int i = 1; i <= n; i++) {
        cin >> vx[i] >> vy[i];
        comp1.emplace_back(vx[i]);
        comp2.emplace_back(vy[i]);
    }
    sort(comp1.begin(), comp1.end());
    sort(comp2.begin(), comp2.end());
    comp1.erase(unique(comp1.begin(), comp1.end()), comp1.end());
    comp2.erase(unique(comp2.begin(), comp2.end()), comp2.end());
    for (int i = 1; i <= n; i++) {
        vx[i] = lower_bound(comp1.begin(), comp1.end(), vx[i])-comp1.begin();
        vy[i] = lower_bound(comp2.begin(), comp2.end(), vy[i])-comp2.begin();
        g[vx[i]].emplace_back(vy[i]+n, i);
        g[vy[i]+n].emplace_back(vx[i], i);
    }

    phase_1 = true;

    for(int i = 0; i < 2 * n; i++) {
        if((g[i].size() - deg[i]) % 2 == 1) {
            xit = false;
            dfs(i);
        }
    }

    phase_1 = false;

    for(int i = 0; i < 2 * n; i++) {
        dfs(i);
    }

    for (int i = 1; i <= n; i++) cout << (ans[i]?'F':'L');
    cout << "\n";
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    // int T; cin >> T; while(T--)
    solve();
}